Various types of frame constructions have been provided for holding posters, signs, etc. upon flat vertical wall surfaces. These frames were secured to vertical wall surfaces by screws or bolts or by double-sided adhesive tape applied to the rear surfaces of the frames. The screws or bolts passed through the corners of the main vertical wall of the frames. Some of these frames had poster pass-through slots in the top or a side margin thereof into which the poster or sign was passed before the frame was mounted. Once the frame was mounted on the wall, it was sometimes not possible to remove the poster or sign from the frames without the frame being removed from the wall because of lack of clearances to do so. In some cases, the frames were designed to permit insertion and removal of a poster or sign through the opening in the front of the frame. Since the opening had to be made slightly larger than the size of the poster or sign which was to fit into it and it is usually desirable that the margins of the frame cover the margins of the poster or sign, such frames sometimes were designed to have pivoted sections which in their opened position fully opened the front of the frame to receive the poster or sign. The pivoted sections were then returned to their closed positions to cover the margins of the poster or sign. This design was obviously a very costly and cumbersome one.
In frames where anchoring screws were used to anchor the rear wall of the frame, the screw heads often projected from the wall. Since the poster or sign could not be placed over these screws, a poster-carrying backboard insert was sometimes used to carry the sheet material forming the poster or sign and the insert and sheet material carried thereby was then placed into the frame. If one wanted the sign or poster to be magnetically held on the backboard by magnet-carrying areas on the back thereof, the backboard would have to be a magnet attracting metal plate, which added to the weight of the frame.